Iowa State University Evaluates Time by Temperature Holding Times on Swine Barn Entryway Surfaces

Research conducted by Iowa State University shows time by temperature holding times is an effective means of inactivating disease-causing pathogens in swine barn entryways.

To evaluate the effectiveness of using time by temperature holding times in swine barn entryways to inactivate swine disease causing pathogens, researchers with Iowa State University evaluated the survivability of two stains of PRRS and PED on aluminum and cardboard surfaces at various temperatures over various holding times.Swine Health Information Center Executive Director Dr. Paul Sundberg says researchers did find variation.

Clip-Dr. Paul Sundberg-Swine Health Information Center:

We did find a variation between the PRRS virus strains.144 Line 1C was inactivated on aluminum surfaces if you could heat the aluminum to 86 degrees Fahrenheit and hold it for 12 hours.

On carboard that was 86 degrees Fahrenheit for only six hours but, when you go to the PRRS 184 strain, 86 degrees inactivated that strain after 24 hours on aluminum and as quickly as 12 hours on cardboard if you could get the heat up to 104 degrees.For PRRS the issue there is variation.

Bottom line is that, while there is variation there, 86 degrees Fahrenheit for 24 hours looks like it could be effective against multiple different PRRS strains, at least 844 and 144 Line 1C.With PED that 86 degrees on aluminum after six hours was a successful inactivation time and after 12 hours on cardboard.

Dr. Sundberg suggests the take home message is that we can inactivate PRRS and PED using time by temperature procedures on entryways but this should be considered as one hurdle in a series of hurdles that need to put in place to prevent pathogen entry onto farms.